Chapter 5: Molecules and Compounds
 Name molecular compounds.
 Name binary acids.
 Name oxyacids containing an oxyanion
ending in -ate.
 Name oxyacids containing an oxyanion
ending in -ite.

Remember, nearly all molecular compounds
form from two or more nonmetals.

Binary (two-element) molecular compound
names have the following form:
prefix
name of 1st
+ element
+
prefix
+
base name of 2nd
element + ide
When writing the name of a molecular compound
the first element is the more metal-like one
 The prefixes given to each element indicate the
number of specific atoms present
mono- 1
hexa- 6
di- 2
hepta- 7
tri- 3
octa- 8
tetra- 4
nona-9
penta- 5
deca-10

 If there is only one atom of the first
element, the prefix mono- is normally
omitted.
 CO2
▪ The full name is carbon dioxide.
 When the prefix ends with a vowel and
the base name starts with a vowel, the
first vowel is sometimes dropped.
 Vowel is dropped in monoxide but not in
dioxide or triiodide.
 N2O
 The entire name is dinitrogen monoxide.
 CCl4
 BCl3
 SF6
 N2O4
 Write the formulas for each compound:
 disulfur tetrafluoride
 phosphorus pentafluoride
 xenon hexafluoride
 The first step in naming an acid
compound is identifying it as an acid.
 Acids are molecular compounds that
form H+ ions when dissolved in water.
 Acids will always be aqueous (aq)
 They are composed of hydrogen,
usually written first in their formula, and
one or more nonmetals, written second.
 We can categorize acids into two
groups:
 binary acids: those containing only
hydrogen and a nonmetal
 oxyacids: those containing hydrogen, a
nonmetal, and oxygen
 Binary acids are composed of hydrogen
and a nonmetal. The names for binary
acids have the following form:
 HCl(aq)
 hydrochloric acid
 HBr(aq)
 hydrobromic acid
 HCl(g)
 refers to hydrogen chloride molecules in
the gas phase, and not to the acid.
 H2S(aq)
 HF(aq)
 Write the formula of each compound:
 hydroiodic acid
 hydrofluoric acid
 Oxyacids are acids that contain
oxyanions, which can be found in the
table of polyatomic ions.
 These acids are a combination of one or
more H+ ions with an oxyanion.
 The number of H+ ions depends on the
charge of the oxyanion, so that the
formula is always charge-neutral.

The names of acids containing oxyanions
ending with -ite take this form:
 H2SO3(aq) contains the sulfite (SO32−) ion

The names of acids containing oxyanions
ending with -ate take this form:

HNO3(aq) contains the nitrate (NO3−) ion
 HC2H3O2(aq)
 HNO2(aq)
 Write the formula for each compound:
 Nitric acid
 Nitrous acid
 Hypochlorous acid
 Perbromic acid

CO(g)

CaF2(aq)

HF(aq)

Fe(NO3)3(s)

HClO4(aq)

H2SO3(aq)